Fuse for projectiles traversing gaseous and liquid mediums



Jan 29, U

FUSE FOR PROJECTILES TRAVERSING GASEOUS AND LIQUID MEDIUMS Filed Feb. 10, 1953 flvvf/vroli lV/LS AFR/K 6 037175 K04 ER i fl- Ha United States Patent FUSE FOR PROJECTILES TRAVERSING GASEOUS AND LIQUID MEDIUMS Nils Erik Gustaf Kiiller, Karlskoga, Sweden Application February 10, 1953, Serial No. 336,177

Claims priority, application Sweden March 17, 1952 8 Claims. (Cl. 102 73 The present invention relates to a fuse for an explosive projectile device for a trajectory first traversing air and then water. In such fuses it is desirable that a medium flowing against the fuse shall be prevented from penetrating into the interior of the fuse.

The purpose of the present invention is to provide a fuse design which satisfies this requirement.

A device for a fuse of a projectile, intended for firing from one medium to another, Where the fuse is arranged in the front part of the projectile and provided with a releasing device for the actuation by outer forces, is characterized according to the present invention by the said releasing device being movably arranged in a chamber in the projectile and having a part going through a wall of the said chamber, by the said chamber before the actuation being made tight against the said mediumsby the aid of a device, and by the last-mentioned part and the part of the wall which the said part passes being shaped in such a way that upon actuation of the releasing device these parts are tightly locked to each other.

The invention will be described more in detail in connection with the enclosed drawing, where the figure shows a device according to the present invention.

In the figure, 1 is a nose-shaped member which has the form of a cap. The lower edge of the nose 1 rests against a flange ring 2, arranged at a cylindrical tube, consisting of the two parts 3 and 4. The upper end of the tube 4 is covered by a member 5. Parts 3, 4 and 5 constitute a closed casing. From the upper side of the member 5 two cylindrical portions 6 and 7 are extended. The parts 2 and 47 can be made of a single piece and constitute a cup member. The member 5 is in its middle provided with a through hole 8. The external surfaces of parts 4, 5 and 7 together with the internal surface of the nose 1 form a chamber. A channel 9 extends from the top of the nose 1 into the said chamber. It is, of course, also possible to replace this channel by a number of channels with smaller cross sections. In the upper end of the channel 9, a groove 10 is provided. This groove is intended to receive a protective plate which can easily be removed. It is also possible to use a plug provided with threads instead of a protective plate. The groove 10 must then be replaced by threads. From the lower part of the outer wall of the nose 1, a narrow bore 11 extends into the chamber. This narrow bore has a direction such that a medium flowing against the nose 1 in an axial direction in relation to the symmetry axis of the nose is not able to flow through the bore 11. It is also possible to use a number of bores of the same character as the bore 11. At its upper end the tube 7 is provided with internal threads and a flange. A sealing plate 12 rests against the said flange, which plate can be made for instance of phosphor bronze. The said plate is pressed against the flange by means of a plate 13, which is provided with threads to fit into the threads mentioned before, and which is screwed into the upper end of the tube 7. The plate 13 is provided with a 2,779,285 Patented Jan. 29, 1957 number of through holes 14 and 15, two of which are visible in the figure. In the hole 8 there is a bar 16, which is kept in a predetermined position by a pin 17 penetrating the bar and into member 5. In its upper part the bar 16 is provided with a member 18, the surface of which is conical. This surface is intended to engage a second conical surface on a liner 19 fitted in cylinder portion 6. The liner 19 may be made of lead or some other material with similar properties. Instead of using the liner 19, it is possible to give the internal surface of the tube 6 the same shape as the said conical surface of the liner 19. At the member 18 there is fastened a circular plate 20 with a diameter nearly the same as the internal diameter of the cylindrical portion 7.

The device described above functions as follows. It is presumed that the device shown in the figure is fastened to a projectile moving from one medium to another, i. e. from air to water, and that the protecting plate in the groove 10 has been removed just before firing. During the movement of the projectile through air, there will 7 always be air in the chamber formed by the internal wall of the nose 1 and the external walls of the parts 4, 5, and 7. When-the projectile enters the water, the air of the chamber will be pressed out through the channel 11 by the water. In order to press down the plate 20 with the parts 16 and 18, it is necessary that the water act on the plate 20 through the holes 14 and 15 and the tightly fitting plate 12-with a force exceeding the force required to shear'off the pin '17. When this force is built-up in the chamber, the pin 17 is sheared oif, and the plate 20 with the parts 16 and 18 are axially displaced by the influx of water at the same time as the tightly fitting plate 12 is destroyed. The water is prevented from penetrating into the casing of the projectile through the hole 8, by the tight engagement of the conical surfaces of parts 18 and 19 when the plate 20 is pressed down by the water and locked parts 18 and 19 in the engaged position. One of the two conical surfaces may be of such a material that the two conical surfaces lie close to each other. It has been found advantageous to make one surface of lead or another material with the same or nearly the same properties.

I claim:

1. A fuse for an explosive projectile designed for a trajectory successively traversing a gaseous medium and a liquid medium, the said fuse comprising a closed casing, an open ended hollow cap joined to said casing so as to form a chamber bounded by the inner wall of said cap and a wall of said casing, said wall including apertures leading into the casing fuse actuating means including an actuating member slidably extending through an opening in said casing wall, a fragile closure means within said casing interposed between said apertured casing wall and said actuating means for preventing the ingress of either medium into the casing through said apertures, retaining means retaining said member in a fixed position relative to said wall, the trajectory part of the projectile through the liquid medium causing a pressure built-up in said chamber effecting a fracture of said closure means whereby the resulting ingress of liquid medium causes a displacement of the actuating member against the action of said retaining means, and sealing means interposed between said actuating member and the surrounding easing wall portion for effecting a tight seal between the said casing wall portion and the actuating member in said displaced position of the latter thereby preventing the ingress of liquid medium into the casing, said sealing means comprising coacting surfaces on the actuating member and the casing wall portion surrounding said member, the said coacting surfaces being spaced apart in said retained position of the actuating member and in sealing engagement in the displaced position thereof.

2,779,285 7 V x r 2. A fuse according to claim 1, wherein the said coacting surfaces are conical surfaces having a slant relative to each other such that the two surfaces are in wedging engagement in said displaced position of the actuating member.

3. A fuse according to claim 2, wherein at least one of said coacting surfaces is lined with a pliable material for effecting a tight seal therebetween.

4. A fuse according to claim 3, wherein the said lining comprises lead.

5. A fuse according to claim 1, wherein the said retaining means comprise shear means set to yield in response to a pressure built up above a predetermined value.

6. A fuse according to claim 1, wherein the said closure means comprise a fragile diaphragm means breakable above a predetermined pressure. a

7. A fuse according to claim 6, wherein the said diaphragm means is made of phosphorous bronze.

8. A fuse for an explosive projectile designed for a trajectory first traversing a gaseous medium and then a liquid medium, said fuse comprising a closed casing, 21 cup-shaped hollow member rising from one wall 'of said casing sealed thereto, the bottom wall of said cup member being made of a material breakable in response to a predetermined pressure, an open ended hollow nose joined to said casing wall so as to form a chamber bounded by the inner wall of said nose and said casing wall and including said cup member, the Wall of said nose including an aperture forming an egress from the chamber having a cross-sectional area less than that of the open nose end, fuse actuating means within said cup member, said actuating means including an actuating member slidably extending into the casing through the casing wall portion circumscribed by said cup member, retaining means retaining said member in a fixed position relative to said wall portion, the trajectory part of the projectile through the liquid medium causing a pressure build-up in said chamber effecting a fracture of said breakable cup wall whereby the resulting ingress of liquid medium into the cup member causes a displacement of the actuating member against the action of said retaining means, and sealing means interposed between said actuating member and the surrounding casing wallportion circumscribed by the cup member for effecting a tight seal between the said casing wall portion and the actuating member in said displaced position of the latter thereby preventing the ingress of liquid medium into the, casing through said opening, said sealing means comprising coacting surfaces on the actuating member and the surrounding casing wall portion, the said coacting surfaces being spaced apart in said retained position of the actuating member and in sealing engagement in the displaced position thereof.

References Cited in the file of this patent UNITED STATES PATENTS 1,319,282 Huber Oct. 21, 1919 2,462,305 Catlin Feb. 22, 1949 2,601,245 Bowersett June 24, 1952 2,626,568 Podnos et a1. Jan. 27, 1953 FOREIGN PATENTS 307,066 Germany June 2, 1920 39,504 France Aug. 11, 1931 501,654 Great Britain Feb. 28, 1939 

